Method of constructing pneumatic tires



F. S. DICKINSON.

METHOD OF CONSTRUCTING PNEUMATIC TIRES.

APPLICATION FILED FEB. 26, 1915.

1,4205 1 1', Patented Jun 20, 1922.

2 SHEETS-SHEET lv v F. S. DICKINSON.

METHOD OF CONSTRUCTING PNEUMATIC TIRES.

APPLICATION FILED FEB. 26, 1915.

1,4201; 1 1. Patented June 20, 1922. fl/g i 1 structing v casings ofpneumatic tires,

piled,

rim bead and the UNITE 5 rrmnarcx' s. DICKINSON, ormiw YORK, 11. Y.

mrmnopor cons'muc'rme rnmuma'rrc Trans.

To all whom it may concern:

Be it known that I FREDRIOK S. DICKIN- SON, a citizen of the ll-nitedStates, and resident of New York, in the county and State of New York,have invented certain new and useful Im rovements in .Methods of Conlneumatic Tires, of which the following is a specification.

structing pneumatic tires such as are now commonly used uponautomobilesand other vehicles and which comprise an elastic shoe orcasing whichconstitutes the outer portion and tread of thetire and encloses theinner air tube and which has an internal textile body fabric or carcass.

My improvements have particular relation to that class of such tireshoes or casings in which the internal body fabric is of the cord typeand made up Of' cords or threads laid to cover the circumferential areaofthe shoe or casing, in contradistinction to woven fabrics.

In the usual method of constructing such cord or thread body fabrics forthe shoes or as now generally employed, the cords or threads, arebunched, crowded, packed and distorted at the portion of the bodyfabricwhich extends at the sides and rim edges of the shoe or casing, whichconditions arise from the neces sity of equalizin or compensating forthe progressive varia le difference in the circumference of the shoe orcasing at all points of its area between the edge at the tread orperiphery. The

packing and distortion of the cords or threads, as just mentioned, toequalize orcompensate for the differential circumference, not only,fractures and weakens the fibers of which the cords or threads arecomposed but precludes that uniformity of tension which is requisite todurability in the life or service conditions of the tire.

Heretofore, in some methods of constructing the so-called cord tires ofthe class to which my improvements relate, the differentialcircumference has been equalized or compensated for by flattening thecords or threads and laying up the narrow edges of the cords, which arethus produced, against or at right angles 'to the core or mandril onwhich the cord fabric is formed, at that portion thereof whichcorrresponds to the side edge or rim bead of the tire,

Specification of Lettersratent. Patented J line 20, 1922.

I Application filed February 26, 1915. Serial .No. 10,667.

thereof lays againstor parallel to thaiaportion of the core or mandrilwhich corre- .sponds to the periphery or tread portion. of the tire.While this method of construction compensates for the variablecircumference, This invention relates to methods of--con,

in that it serves to extend over or cover the full variablecircumferential area of the tire shoe or casing, the flattening of thecords or threads fractures the fibers thereof and thereby materiallyweakens fabric, and the twisting not only precludes the maintenance of.uniformity of tension throughout the length of the cords or threads butit creates frictional actionbetween the cords by displacing the positionthe of the twist when the tire is'depressed or flexed in service.

The object. of my improved method of constructing the casings ofpneumatic tires is to effectively overcome the conditions andobjectionable features above I set forth and produce an improved tire ofthe cord type in which the body fabric will retain all the initialstrength of the fibers from which the cords or threads'aremade up andwill ensure the requisite uniformity cially to the method ofconstructing the body fabric or carcass by laying or winding the cord inan initial position with relation to a support, to produce a fabric web,and there after shifting saidcord to change the angle of lay thereof tothe position in which the cord elements are associated in-the comoftension,

and my present improvements relate espe-- pleted carcass which isproduced by said 7 improved method.

In the drawings- 5 1. Figure'l is a perspective view, partly in section,I cord body fabric according to my improved method.'

- Fig. 2 1s a cross-section of the core or mandril over which the cordsor threads are. laid in constructing the fabric accordmg ing the initialpositional relationship of the cords thereto.

Fig. 3 is a detail cross-section illustrating the single-plyfabriciproduced by my improved method, in its contour as it would be ina finished tire under inflation.

Fig. 4 is a plan view illustrating-the po-" sitional relationship of thecord 01. threads,

of a single-ply construction of the to my improved method,-andillustratas laid over the core or mandril on'which the fabric is formedafter the shifting method which changes the angle of lay.

Fig. 5 is a perspective view, partly in section, illustrating acompleted tire shoe or casing constructed according to my improvedmethod and showing a construction thereof in which superimposed plies ofthe cord body fabric are employed.

Fig. 6 is a plan view corresponding to Fig. 4 and illustrating amodified construction according to my improved method, in which a tapemade up of-a group of cords or threads is employed and laid in lieu of asingle cord, and showing the angular lay of the tape after the shiftingmethod which changes the initial position.

Fig. 7. is a detail cross-section on the line mm, Fig. 6.

Corresponding parts in all the figures are denoted by the same referencecharacters.

This present application is directed especially to. the improved methodof shifting I the cord to change the angle of lay, as before referred toand hereinafter described, and comprises the claims of an interferenceissue upon which priority was awarded applicant against one James A.Swinehart on applications filed by said Swinehart respectively April 17,1915, Serial No. 21,980, and

December 16, 1914, Serial No. 877,508, the.

general subject-matter of applicants improved method having been dividedfrom this application in interference and filed as a separateapplication on August 1, 1918, Serial No. 247,713, which divisionalapplication matured into Patent No. 1,294,063, granted February 11,1919.

Referring to'the drawings, 1 designates the tire shoe or casing, whichcomprises the internal/fabric body, 2, and the elastic external portionconstituting the tread, 3, whichcasing incloses the usual air tube andis held in connection with the wheel rim in the usual manner.

The improved cord body fabric, as constructed according to my improvedmethod, is constituted by the cords or threads, 4, which are laid toextend over or cover the entire circumferential area of the shoe orcasing, the construction being preferably produced by the laying of acontinuous.

, or looped, as at 5, at the terminal side edges or rim-bead portion ofthe tire, and at said inezoen loops they are laid directly over eachother, as at 6, from which point they are spread or diverged orradiated, in a gradual and continuous positional relationship, as-at 7at the circumferential side portions of the tire, so that theyrelativelyspread andthe under cord gradually emerges from beneath theupper cord, until they extend over or cover the full .area of thegreatest circumference of the tire at the tread or peripheral portionthereof, as at 8.. The cord body fabric, under the improved method ofconstruction above described, thus extends over or covers the full areaof the'varying or differential circumference of the tire shoe or casing,without packing or distortion or flattening or twisting of the cords orthreads, and equalizes or compensates for the differential circumferenceat all points thereof. It will be noted that in their final position oflay the cords or threads extend ona line diagonal or at an oblique angleto the transverse or segmental cross-sectional plane of the tire asillustrated in Figs. 4L and 6. In a cord body fabric employing singlecords 90 or threads, as constructed according to the general conditionsof the method herein shown, the gradually diverging or radiating Y cordshavea position closely side by side at that portion of the fabric whichis at the point of greatest circumference of the tire, which is wherethe cords cross the tread portion or periphery, as shown in Fig. 4'. Incarrying out the general method of constructing the cord body fabric,according to the conditions of my invention as herein set forth, thecords are preferably laid over a suitable core or mandril, 10, of suchsize and form as to conform to the inner contour of the finishedtireshoe or casing, which core is suitably mounted rotatably to beadvanced instep movementsgraduated according to the diameter of the cordor thread used. At opposite sides of said mandrel, are mounted range orhoops, 11, which are initially held in position a suitable distance awayfrom the core, as shown in Fig. 2, the relative osition of said ringsand core being sue that the I cords or threads when laid will have aproper lengthtoextend over the periphery of the core and downwardly ateach side thereof a suflicient distance to permit the rings 11 and thelooped portions '5 of the cords to form the side edges or head of thetire shoe or casing. The cords or threads are then laid in a continuouslength passing under and around one of the siderings 11 and from thenceover and across the periphery of the core 10 and under and around theother side ring 11, the loops 5 being formed around the rings 11 and thegradual divergence or radiation of the' cords in their angular positionin the completed fabric or carcass being from this point over and acrossthe periphery of the core, as at 7-8 (Fig. 4). The laying of the cordsin the manner just indicated is continued until the fabric correspondingto 5 the entire circumference of the tire shoe or ished fabric willconform to the circumfer ential annular and segmental cross-sectionalcontour of the finished shoe or casing. a plurality of plies are to beemployed in the body fabric, as shown in Fig, 5, the succeeding pliesare laid up in like manner as that just described, but the shifting ofthe cords in the succeeding ply is such thatfi they extend preferably atan oblique angle or diagonal position opposite to that of the precedingply.

When the desired number of plies have been laid up in the foregoingmanner, an elastic bond is created between all the cords or threads bythe application of a caoutchouc filler, this being preferablyaccomplished by impregnating the entire body with soluble rubber in avacuum chamber. There is thus produced a homogeneous caoutchouc andfabric carcass conforming to the contour of the finished shoe or casingand comprising a casing of rubber in which are embedded reinforcingcords or threads. After completion of the homogeneous cord fabric andcaoutchouc carcass or casing, as just described, the latter 1s placed inassociation withthe elastic external portion of the shoe or casing,which incloses the body fabric or carcass and forms the usual cushionand tread 3 of the tire, and the complete shoe or casing thus producedis vulcanized or cured in the customary manner. I V

In carrying out the improved method of constructing the cord bodyfabric, as herein set forth, I do not restrict myself to any particularmechanism for laying up or forming the cord skeleton or fabric which isproduced by my method, as this may be accomplished in various ways. Forinstance, the cords or threads may be initially wound or looped over thetwo rings 11 with the latter positioned a proper distance apart to allowsufficient length of cord extending between them to form the width ofbody fabric which is to pass at the determined oblique angle from theedge or bead of one side of the tire to the edge or bead of the otherside; then, into the annular completed ring or hoop of the cord fabricso formed upon the side rings 11, a sectional core or mandril isinserted, with the periphery thereof midway between the two side rings11. The conditions of construction with the mechanism as above de- 3scribed are illustrated in Fig. 2, and in car- If scribed and as shownin fabric rying out the improved method as comprised in my presentinvention', "in relation to the mechanism including the rings, thelatter serve as a support for the fabric web of the cord tire skeletonwhich is spirally Wound onto such support. cords are in a planeextending transversely of the annulus of the core, as shown in Fig. 2,after which said side rings turned in opposite directions to lay thecords over the core at the proper oblique angle in the relative positionas hereinbefore do- Figs. 4 and 6 in which the cords overlay each, otherat the side bends or loops 5 and gradually diverge or radiate therefromso that the under cord emerges from beneath the upper cord, as at 7,until the cords lay parallel and side by side, as as 8, over the area ofthe peripheral portion of the core.

In their initial lay the In carrying out the improved method, the

11, upon which the cords or threads are looped or wound, in oneprestrands in opposite directions suitable supporting means, to

ferred mechanism for carrying out my improved method of construction,may be ofany suitable material, such as a metallic wire or a textilecord, and they preferably remain within the completed fabric, so thatthey form beads or retaining rings within the selvage edge of the fabricat the loops 5 '(Fig. 5), at the side edges or beads of the shoe orcasing, by which'the tire is held in position on the wheel rim.

Under some circumstances of tire construction, according to my improvedmethod, a single ply of cord body, fabric, in Figs. 1 and 4;, may beemployed, but under some circumstances a plurality of layers or plies orlaminations of the fabric may be employed, as shown in Fig.- 5, andwherea plurality of plies are employed the respective plies arepreferably laid under the shifting action to change their angle toextend in opposite directions in their diagonal or oblique lines withrelation to the segmental cross-section of the shoe or casing, reversepositions of the plies are best adapted to equalize all stresses orstrains when the tire is depressed or flexed in service.

Under some circumstances of construction, according to my improvedmethod, in lieu of laying a single cord or thread (as as shown its 3which I provements.

may be laid from a tape made up of groups or multiples of single cordsor threads, as'

in the modification illustrated in Figs. 6 and 7. The tape, shown at 12,in this method of construction, is laid and shifted in thesame manner asthe single cord or thread construction, with the side loops, 5,eXtendinga-round the rings or hoops 11, at Which point the tapesdirectly overlie each other and from which point the tapes graduallydiverge or radiate, as at 7 so that the under tape gradually emergesfrom-beneath the upper tape and, the tapes overlie and extend over orcover, as at 8, the in creased circumferential area of the peripheral ortread portion of the shoe or casing. In view of the increased width ofthe tape unit, in contradistinction to the single cord construction asshown in Fig. 4, .it is not necessary that the tapes lay side by side atthe peripheral or tread portion, as. is the case with the single cordmethod of con-' struction, but the tapes are'laid to overlap a suitableportion of their respective widths, as shown at 14, 'atthe peripheralortread portion, which overlapping construction fully equalizes andcompensates for the differential diameters in the same manner as thesingle cord construction and at the and described, as it is manifestthat variations therein may be resorted to in the adaptation of themethod of constuction to varying conditions according to the type ofpneumatic tire casing to which the cord body fabric as produced by mymethod is to be applied,'without departing from the spirit and'scope ofmy invention and im 1 therefore reserve the right to. all suchvariations and modifications as properly fall within the scope of myinvention and the terms of the following claims.

Having thus described my invention, ll claim and desire to secure byLetters Patent:

1. The method of constructing the internal body fabric for the shoe orcasing of pneumatic-tires of the cord type, which consists in anchoringtwo series of textile cord elements at the rim-bead portion in suchposition that the cord elements of one series overlie the vcord elementsof the other series at an angle tothe annulus of the tire, and spreadingor diverging said cord elements from said overlyingposition in a gradualpositional relationship in which: the under cord elements of one seriesgradually emerge from beneath the outer cord elements ofthe other seriesand lay side by side beyond said emerging portions at thecircumferential side, portions of the tire and conjointly produce, atextile cord carcass which covers the space area at the tread emergesfrom beneath the upper cord and the spreading cords lay side by-sidebeyond said emerging portions andconjointly cover. the space area of therogressive variable circumference of the tire at the side and tread orperipheral portions thereof.

3. The method of making a tire skeleton, which comprises winding cordspirally around a support to produce a fabric web,- and thereaftershifting said cord to change 1 the angle of the cord elements relativeto the sides of'said fabric web.

4. The method of making a tire skeleton, which comprises winding 'cordspirally around a support to produce an unwoven fabric web, andthereafter shifting said cord to change the angle of the cord elementsrelative to the sides of said fabric web.

5. The method of making a tire skeleton, which comprises winding cordspirally onto a pair of supports, and thereafter shifting one of themarginal edges of the structure to change the angle of the cord elementsre-- lative to the sides of said structure. 6. The method of making atire skeleton, which comprises winding cord spirally onto a support toproduce a fabric web, and thereafter shifting a portion of said supportto change the angle of the cord elements relative to the sides of saidfabric web.

-7. The method of making a tire skeleton,

which comprises Winding cord spirallyaround a pair of supportingelements to produce a fabric web,and thereafter shifting one of saidsupporting elements to position the cord elements at an an de reerelative to the sides 0% 8. The method of making fabric tire skeletons,which comprises winding cord said fabric around a pair of strands toproducea fabric e of flesser web, and thereafter shifting said cord toto position the cord elements at an angle 10 position the cord elementsat an angle to to the side edges of said fabric Web. the side edges-ofsaid fabric web. In witness whereof I have signed my 9. The method ofmaking fabric tire name in the presence of the subscribing witskeletons,which comprises winding cord nesses.

around a pair of wire strands to produce a FREDRICK S. DICKINSON. fabricWeb, said wire strands being located Witnesses: at the side edges. ofsaid fabric web, and Jos. REED LITTELL,

thereafter shifting one of said wire strands AGNES LEE.

